Methotrexate-induced Leukoencephalopathy without Typical Restricted Diffusion on Diffusion-weighted Imaging and the Utility of Magnetic Resonance Spectroscopy to Support the Diagnosis.

Methotrexate (MTX) is a common antimetabolite agent that is widely used today in treating leukemia, lymphoma, and osteosarcoma. Its use has been associated with leukoencephalopathy causing seizures, paralysis, and even coma. To achieve the best possible outcome, it is important to be able to make a prompt diagnosis.

Intracranial subdural empyema mimicking a recurrent chronic subdural hematoma.

Intracranial subdural empyema (ISDE) is a life-threatening condition. The risk for ISDE increases in patients that have undergone prior intracranial procedures. The non-specificity in its clinical presentation often makes ISDE difficult to diagnose.